Al Qaeda goes dark

Eli Lake has the story of the day in today’s New York Sun: “Qaeda goes dark after a U.S. slip.” Lake reports that the September 7 Osama bin Laden video (the one with the funny looking black beard) was picked up by Rita Katz’s SITE Institute and provided to the National Counterterrorism Center:

The head of the SITE Intelligence Group, an organization that monitors Jihadi Web sites and provides information to subscribers, Rita Katz, said she personally provided the video on September 7 to the deputy director of the National Counterterrorism Center, Michael Leiter.
Ms. Katz yesterday said, “We shared a copy of the transcript and the video with the U.S. government, to Michael Leiter, with the request specifically that it was important to keep the subject secret. Then the video was leaked out. An investigation into who downloaded the video from our server indicated that several computers with IP addresses were registered to government agencies.”

As a result of the leak, al Qaeda discovered that its intranet communication setup was not secure, and has shut it down:

One intelligence officer who requested anonymity said in an interview last week that the intelligence community watched in real time the shutdown of the Obelisk system. America’s Obelisk watchers even saw the order to shut down the system delivered from Qaeda’s internal security to a team of technical workers in Malaysia. That was the last internal message America’s intelligence community saw. “We saw the whole thing shut down because of this leak,” the official said. “We lost an important keyhole into the enemy.”
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The founder of a Web site known as clandestineradio.com, Nick Grace, tracked the shutdown of Qaeda’s Obelisk system in real time. “It was both unprecedented and chilling from the perspective of a Web techie. The discipline and coordination to take the entire system down involving multiple Web servers, hundreds of user names and passwords, is an astounding feat, especially that it was done within minutes,” Mr. Grace said yesterday.
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Ms. Katz said, “The government leak damaged our investigation into Al Qaeda’s network. Techniques and sources that took years to develop became ineffective. As a result of the leak Al Qaeda changed their methods.”

Who leaked the video? Lake has a round of denials:

Ms. Katz yesterday said, “We shared a copy of the transcript and the video with the U.S. government, to Michael Leiter, with the request specifically that it was important to keep the subject secret. Then the video was leaked out. An investigation into who downloaded the video from our server indicated that several computers with IP addresses were registered to government agencies.”
Yesterday a spokesman for the National Counterterrorism Center, Carl Kropf, denied the accusation that it was responsible for the leak. “That’s just absolutely wrong. The allegation and the accusation that we did that is unfounded,” he said. The spokesman for the director of national intelligence, Ross Feinstein, yesterday also denied the leak allegation. “The intelligence community and the ODNI senior leadership did not leak this video to the media,” he said.

Brian Ross’s September 7 ABC report refers only to “intelligence sources.” Who might they be?
JOHN wonders: Can we please, finally, have an investigation into a real leak?
UPDATE: Rusty Shackleford persuasively argues that SITE was not the source of the leaked video transcript and that al Qaeda was not prompted to go dark by the alleged leak described by the Sun (and the Washington Post).